Transportation is the act of moving people or goods from one place to another.

Without transportation there could be no trade.

Throughout most of history, transportation was extremely slow and difficult. Prehistoric people travelled mainly on foot. They transported goods on their backs or heads or by dragging them along the ground.

Ships are one of the oldest and most important means of transportation.

A ship is one of the most complicated objects ever made. It is actually a floating city that generates its own fuel and provisions. It can make its own fresh water from the sea and it disposes of its own rubbish.

Trade among countries depends heavily on ships. Many kinds of ships are used to carry the worldâ€™s trade. Giant tankers are used to carry petroleum, vegetable oil, wines and other liquids. Refrigerator ships carry fresh fruits, meats and vegetables. Vessels called â€˜dry bulk carriersâ€™ haul such cargoes as grain, ore and sand. General cargo ships transport everything from aeroplane engines to zip fasteners.

Today, ships are as important as ever to a countryâ€™s prosperity and strength. The worldâ€™s leading trading nations depend largely on ships for imports and exports. Many trading nations have a large â€˜merchant navyâ€™. A merchant navy consists of the commercial or merchant ships of a country.

Cargo ships or freighters can be divided into four groups, according to the type of cargo they carry:

what are called â€˜packagedâ€™

packages or that form a package themselves. Packaged items include such products as chemicals, food, furniture, machinery, motor vehicles, shoes, steel, textiles and wine. Specialized versions of